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S. E. TzamariasS. E. TzamariasHellenic Open Hellenic Open

UniversityUniversity

NNeutrino eutrino EExtended xtended SSubmarine ubmarine TTelescope with elescope with OOceanographic ceanographic

RResearchesearch

Readout Electronics Readout Electronics DAQ & Calibration DAQ & Calibration

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NESTOR TOWERNESTOR TOWER

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• Hamamatsu PMT R2018-03 (15”)

• Benthos spheres

• μ-metal cage

• power supply

Single p.e. conditions

The Detector

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ReadOut Electronics & DAQ Chain

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Signal transmission & ControlShore Laboratory Power supply

PMT signal transmission

low voltage supply (24V) control and monitoring signal transmission

House Keeping Board PMT control Calibration Beakon control PMT HV monitor Power Supply monitors Environmental monitors

Floor Board PMT pulse sensing Majority logic event triggering Single & coincidence rate scaling Waveform capture & digitization Data formatting & transmission FPGA & PLD reprogramming

Ti-Sphere ElectronicsTi-Sphere Electronics

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Input: 12 PMT signals

Delay lines

Configuration parameters PLD

Trigger Logic & Communication FPGAs

5 ATWDs

Floor BoardFloor Board PMT pulse sensing Majority logic event triggering Single & coincidence rate scaling Waveform capture & digitization Data formatting & transmission FPGA & PLD reprogramming

PMT Signal Capture & Digitization

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The LED Calibration System

Frequency

Duration

Light amplitude

20m

20m

• Gain monitoring

• Timing

• Free running Calibration Trigger

• Adjustable Trigger frequency

• Adjustable LED’s light output

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Extensive Lab tests

On single p.e. conditions

Detector Preparation

Calibration at the Lab

L.E.D.Reference

Relative timing

                                

                   

Pulse Height (mV)

LED Calibration Run

Time Difference in PMTs Response

Time (ns)

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Detector Preparation

Attenuation Correction

                                

                  

Reference waveform

Coaxial cable

Electronic delay lines and amplifier

Fourier Transform-ComparisonFrequency (MHz)

Frequency (MHz)

Ph

ase

(rad

)A

mp

litu

de

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Num

ber

of P

.E.s

/ s

r /L

ight

Pul

se Laboratory measurements

PMT Geometrical Factor: 3.46 ·10-4

Transmission Factor: 0.72

Parameterized Angular Profile of the LED emission in air

Estimated Angular Profile of the LED emission in water

LED Angular Profile

Angle (Degrees)

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to the floor board

Data Files

Delete Data Storage

Event samples

Monitor

Offline

fast analysis

DAQ Architecture

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Online Software

Shore Board Downloads the FPGAs & PLD of the Floor Board Broadcasts the 40Mhz clock Receives Data from the Floor Board Transmits Data to the Run Control System

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Event samples

Monitor

Real Time Monitor Environmental

• Thermometers

• Hygrometers

•Compass

•Inclinometer/Accelerometer

• Pressure meter

Electrical

• PMT High Voltage etc

Digitization & DAQ Performance

• Digitized waveforms

• PMT rates

• Trigger rates

• DAQ status

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Real Time MonitorsReal Time Monitors

Sample

448 ns

During deployment

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Waveform ReconstructionWaveform Reconstruction

Sample Offset (ADC counts)Sample

Off

set

(AD

C c

oun

ts)

Before the F.F.T. and the attenuation corrections

After the F.F.T. and the attenuation corrections

Rise Time

16 ns

9 ns Double pulse separation

Time (ns)

Vol

tage

(m

V)

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Waveform Reconstruction

DST Production

Hit DefinitionData Quality Histograms

Sample

AD

C C

oun

ts

40 MHz Clock Waveform Capture

Event by Event Sampling Interval Variation (Constant Temperature)

Time (ns)

RMS=0.006 ns

Software to Hardware Trigger Time Difference (arbitrary time offset)

σ=0.7ns

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single p.e.

LED Run

single p.e. pulse height distribution

two p.e.s pulse height distribution

dark current pulse height distribution

sum of the above

Data from a depth of 4000 m

Calibration using the natural radiactivity (K40)

Calibration

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Calibration Data Analysis

Calibration Database Quality Histograms

LED Calibration Data

Gain Monitors

Data from a depth of 4000 mCalibration Run

Time Difference (ns)

Nu

mb

er o

f E

ven

tsN

um

ber

of

Eve

nts

Time Difference (ns)

<Δt>: 0.6 ± 0.1 ns

σ : 3.3 ± 0.1 ns

<Δt>: 0.2 ± 0.1 ns

σ : 3.3 ± 0.1 ns

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Data from a depth of 4000 mCalibration Run

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Data from a depth of 4000 mSingle PMT Rates

Trigger: ≥4fold Coincidence

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Data from a depth of 4000 mTrigger Studies

Preliminary

Coincidence Level

Coincidence Level

Tri

gg

er

Ra

te (

Hz)

To

tal

Ch

arg

e i

ns

ide

th

e T

rig

ge

r W

ind

ow

Experimental Points

M.C. Estimation (Atmospheric muons + K40 )

Data Collected with

4fold Majority Trigger

Thresholds at 30mV

(1/4 P.E.)

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Data from a depth of 4000 mTrigger Studies

Preliminary

Coincidence Level

Coincidence Level

Tri

gg

er

Ra

te (

Hz)

To

tal

Ch

arg

e i

ns

ide

th

e T

rig

ge

r W

ind

ow

Experimental Points

M.C. Estimation (Atmospheric muons + K40 )

Data Collected with

4fold Majority Trigger

Thresholds at 120mV

(1 P.E.)